1. Field of the Invention
The present invention relates to a stress relieved assembly for dissipating heat from a semiconductor chip, comprising a substrate, a semiconductor chip, and a thermally conductive member which is brought into contact with the chip.
2. Discussion of Related Art
Semiconductor chips heat up when powered up and operated. For this reason, the semiconductor chips are usually mounted against a thermally conductive plate which transfers heat away therefrom, usually to a heat sink of some sort.
FIG. 1 of the accompanying drawings illustrates an assembly 1 of the prior art comprising a substrate 2, a semiconductor chip 3 located on the substrate 2, and a thermally conductive plate 4 thermally coupled to the semiconductor chip 3. The semiconductor chip 3 may be connected to the substrate 2 by means of an array of solder connections 5. A layer of thermally conductive material 6 may be located between the semiconductor chip 3 and the thermally conductive plate 4. The assembly 1 is held together by means of a clamping structure (not shown) which exerts a clamping force F on the assembly 1. A certain amount of shock and vibration occurs during transportation of the assembly 1, tending to move the thermally conductive plate 4 away from the substrate 2. The clamping force F is sufficient to a hold the assembly 1 intact during normal shock and vibration. The clamping force F may, however, be of a magnitude which may cause damage to the semiconductor chip 3 or the solder connections 5. The layer 6 has some damping effect against shock and vibration. The layer 6, however, has better damping under reduced clamping forces.
It would therefore be desirable to reduce the force acting on the semiconductor chip 3, the solder connections 5, and the layer 6 while still holding the assembly 1 together.